Converter In-Rush Thermistors etc, UPDATE -4
UPDATE on 17 Nov, Update 2 on 22 Nov, Update 3 on 16 Jan 14, Update 4 on 19 Oct 14. --------------- In a recent thread there was mention of how you can wreck your gizmo (in my case a converter) ...
Forum Discussion
BFL13 wrote:
I have redundancy in having other chargers I can use until I repair this one again. If I have two in parallel, it was stated that reduces the R by half if they are sharing so that would be a negative if I have that right.
Yes. Initially, the two will pass twice as much current. Quickly, the sharing will diverge and one will steal most of the current. It might be beneficial if your device has certain timing requirements. It will charge the caps faster and they will share some of the initial load. I doubt it's necessary.
So the latest thinking must be that the 2R025 instead of the 5R 020 isn't such a good idea if the problem is all at start -up and I need more R and higher J?
I haven't done much design work, but from what I've read here, 2 ohms should be sufficient. That said, if it's failing, and you don't think it's a one bad component problem (it's failed twice?) I doubt 5 ohms would be a problem.
The converter steady state while at 100a is supposed to be 13a or at least it is rated to use a 15a circuit, being PF corrected. There is a 10R 15a but I am dubious of that 15.
If there were a 10R 025 that would be nice.
You can put them in series just fine. That would give you a 10R 025. The initial resistance would double, and both can handle the current.
But then what about the business where if you are sitting there on shore power for weeks at 13.6v and mention that the higher R could leave the thermistor doing a slow cook?
The initial resistance isn't the same as steady state resistance. If it's rated for your steady state current, it should handle it. If it's failing at turn on, not while running for a long time, don't worry about it.
